JP2004330328A

JP2004330328A - Builtup broach and broaching method

Info

Publication number: JP2004330328A
Application number: JP2003127115A
Authority: JP
Inventors: Soichi Sumiya; 宗一角谷; Yasuhiro Murai; 康弘村井
Original assignee: Nachi Fujikoshi Corp
Current assignee: Nachi Fujikoshi Corp
Priority date: 2003-05-02
Filing date: 2003-05-02
Publication date: 2004-11-25
Anticipated expiration: 2023-05-02
Also published as: JP4330117B2

Abstract

<P>PROBLEM TO BE SOLVED: To prevent chipping of the mutual abutting surfaces of a plurality of carbide assemblies of a carbide builtup broach, and to reduce inclination to improve accuracy. <P>SOLUTION: This builtup broach 1 comprising the plurality of carbide assemblies 31, 41 is provided with one or more collar parts 9 made of alloy steel to divide a fitting part 4. The assemblies are disposed on both sides of the collar part, and both ends are clamp-fixed by fixing members 7, 8. The fixing member on the front grip part 2 side is provided with a guide part 7b. The abutting parts 41, 9b, 9a, 31b of the collar part and assemblies, and the abutting parts 31a, 7d of the assembly and the fixing member with the guide part, are provided with rotating direction positioning means 41c, 9d, 9c, 31d, 31c, 7e. One or more of the collar parts and fixing members are positioned and stuck to a body. Further, the collar part is provided at one part and fixed to the body, and the abutting surface is made a plane right-angled to an axis or a coaxial conical surface. A high hardness material with a hardness 45 HRC to 65 HRC is machined by such a builtup broach. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は本体の外周に軸方向に多数の切れ刃を配置されたブローチであって、特に切れ刃の材質が超硬合金である（超硬）組立ブローチに関する。さらに、被加工材料が焼き入れ後の例えばロックウエル硬さで５０ＨＲＣ以上の高硬度材の加工に適した組立ブローチに関する。
【０００２】
【従来の技術】
従来のブローチ加工では、被加工物（以下、ワークという）の硬度が２０ＨＲＣから３０ＨＲＣ（ロックウエル硬さＣスケール：以下同じ）以下のワークを対象に行っている。このためワークはブローチ加工後、硬度を上げるための熱処理をされるものが多い。このときの焼き入れ部の硬度は６０ＨＲＣ前後であり、浸炭深さは約１ｍｍである。しかし、浸炭焼き入れすると熱処理歪みが発生するので、予め熱処理の変形を考慮して狙い形状を決め、焼き入れ前のワークを加工していた。しかし、変形量が不安定なため、例えば焼き入れ後のインボリュートスプライン部の精度（径寸法、歯筋、ピッチなど）が目標形状にならない等の問題があった。そこで、これを解決する手段として、特許文献１に記載のブローチにおいては、図９，１０に示すように、前つかみ部２に続いて設けられた案内部７ｂを有する固定部材７、固定部材から後つかみ部３に延出する嵌合部４を有する本体５１に中空円筒状の超硬合金材料の切れ刃３２，４２を有する組立体３１，４１を後つかみ部３と嵌合部４との間に設けられたねじ６にダブルナット８を螺着させて挟持嵌合固定した構造の組立ブローチ５０が示されている。この組立ブローチは、ワークの熱処理歪みが大きく、削りしろを大きくとる必要がある場合などは、必要なブローチ長さが長くなるため、中空円筒状の超硬合金材料の切れ刃を有する組立体４１，４２を２本以上ブローチ本体５１の片側（後つかみ部側）から順に挿入し、ダブルナット等の固定部材８により組立体を挟持固定する構造となる。
【０００３】
【特許文献１】特開２００２−１３７１１８号公報
【０００４】
【発明が解決しようとする課題】
しかしながら、超硬合金材料の切れ刃３１，４２を有する組立体３１，４１を２本以上順に挿入して組み付けると、ブローチ加工による振動が原因となって、組立体の合わせ面（当接面）３１ｂ，４１ａにチッピング、欠けを引き起こすという問題があった。また、組立ブローチの組み付け後の傾きは、一方の組立体の端面の直角度が悪いと、他方の組立体の傾きに影響する。即ち、相互の直角度の誤差が、組み付け後のブローチの傾きに影響しあうため、組立体が１本だけの場合に比べ、良好な組み付け精度（ブローチ傾き）が得られないという問題があった。このことが、加工精度、特にスプラインの歯筋精度、直角度に悪影響を及ぼしていた。
【０００５】
本発明の課題は、かかる従来技術の問題点を解決するためになされたものであり、切れ刃を有する組立体が２本以上必要な組立ブローチにおいて、ブローチ加工振動による組立体当接面のチッピング、欠けを引き起こさないブローチを提供するものである。さらに、組み付け後のブローチの傾きが少なく、組立体が１本の場合と同等の性能を発揮できるブローチを提供するものである。
【０００６】
【課題を解決するための手段】
本発明者等は研究の結果、特許文献１に示されたブローチ工具において組立体を２本にしたものを用いて、硬度が６０ＨＲＣのワークの加工試験を行った結果、ブローチ加工による振動が原因となって起こる、組立体の合わせ面のチッピング、欠けは、切れ刃を有する組立体を合金鋼とした場合では起こりにくいが、超硬合金とした場合に発生しやすい点に着目し、接触面のあたり（接触状態）によっては、部分的に高い応力がかかりチッピングが発生すると考え、組立体の合わせ面に、組立体よりも硬度の低い合金鋼を挟み込むようにして緩衝作用を持たせればよいと考えた。この考えにより、本発明においては、前つかみ部を有する多数の切れ刃を寸法順に配列した内面ブローチであって、前記前つかみ部を有する合金鋼の製本体は前記前つかみ部の反対側に棒状の嵌合部を有しており、前記嵌合部に切れ刃を有する中空円筒状又はリング状の超硬合金製の組立体が複数嵌合固定されている組立ブローチ工具において、前記嵌合部を分割する１以上の合金鋼製の鍔部（間座）を備え、前記鍔部の両側に前記組立体が分割配設され、前記組立体と前記鍔部とを前記組立体の内の最外側の２つの組立体の最外側端面にそれぞれ当接して挟持固定する合金鋼製の固定部材が配設された組立ブローチを提供することにより前述した課題を解決した。
【０００７】
即ち、２本の超硬合金の組立体からなる部分と合金鋼からなるつかみ部を有する本体を一体に組み付けて一本のブローチとし、複数の組立体の間に、合金鋼の鍔部（間座）を配設するようにしたので、硬度の高い超硬合金同士の接触部が無くなり、比較的硬度の低い合金鋼が緩衝材となって、接触面のあたりのばらつきにより、部分的に高い応力がかかることは無くなり、チッピング、欠けの発生を防止するものとなった。なお、固定部材以外の全ての組立体間に鍔部を設けるのが好ましいが一部であっても良い。
【０００８】
また、案内部は切れ刃がなく、ワークに対して硬くする必要もなく、位置決めを容易にしたい。そこで、請求項２に記載の発明においては、前記前つかみ部側の前記固定部材は、被加工物（ワーク）に設けられた前加工溝に嵌合可能に長手方向に延びた案内部を設けた組立ブローチとした。これにより、ワークの前加工溝に案内部が嵌合してワークとブローチとの位相合わせ、位置決めが自動的になされる。さらに刃部を有する円筒状の超硬合金の組立体と合金鋼製の固定部材の案内部はワークの加工諸元に応じて交換できるので、多種ワークへの対応が容易である。また、案内部の先端部を縮径するテーパ形状をもつようにすればより容易に嵌入できることとなる。
【０００９】
さらに、請求項３に記載の発明においては、前記鍔部と前記組立体との当接部、及び、前記案内部を有する固定部材と前記組立体との当接部には、各々、回転方向位置決め手段により回転方向に回らないように互いに位置決めされ、かつ前記鍔部又は前記固定部材の内１以上が前記本体に対し回転しないように前記本体に位置決め又は固着するようにした。これにより、前つかみ部を有する本体と、本体と固定された鍔部又は固定部材に対して、鍔部、組立体、固定部材が互いに回転しないように位置決めされているので、本体、固定部材、組立体、鍔部の全てが固定される。従って、ブローチの前つかみ部を回転角が同じになるよう規制してつかむことにより、案内部、複数の組立体に設けられた刃部の回転位相決めができる。これにより、ワークの回転方向を適切に位置決めすれば、ワークの前加工溝に案内部、ブローチ刃部の回転位相を合わせることができる。
【００１０】
また、本体への固定はできるかぎり確実にしたい。そこで、請求項４に記載の発明においては、固定部材のいずれか一方を本体に一体に形成するようにした。これにより、組立体、鍔部の回り止めが確実にされる。
【００１１】
一方、本発明者等は前述したと同様に、組立体２本を用いたもので硬度が６０ＨＲＣのワークの加工試験を行い加工精度の評価をするにあたり、特にスプラインの歯筋精度、直角度とブローチの組み付け状態に着目したところ、組立体が２本の場合は、１本の場合に比べて、超硬刃を有する円筒状のブローチの本体に組み付いた姿勢の傾きが大きく、加工されたワークのスプラインの歯筋精度、直角度が悪くなると言う知得を得た。これは前述した合金鋼製の鍔部が本体と分離している場合でも同様であった。この知得により、請求項５に記載の本発明においては、前記鍔部を１箇所のみに設け、かつ本体に一体にし、前記組立体と前記鍔部との当接面及び前記組立体と前記固定部材との当接面が軸直角平面又は同軸の円錐面にされた組立ブローチを提供することにより前述した課題を解決した。
【００１２】
即ち、超硬合金の組立体からなる部分と合金鋼からなる前つかみ部を有する本体を嵌合部で嵌合させ一体に組み付けて一本のブローチとする組立ブローチにおいて、嵌合部を分割する本体と一体の合金鋼製の鍔部が設けられ、前つかみ部側より、前つかみ部側の組立体を組み入れ、鍔部の軸直角平面又は同軸の円錐面で当接させ、もう他方側の組立体は後つかみ部（前つかみ部の反対側）から鍔部に軸直角平面又は同軸の円錐面で当接させるように組み入れ、さらに両端を固定部材で挟持固定するようにしたので、超硬合金の組立体の端面直角度が、もう一方の組立体の組み付け後の傾きに影響することはない。したがって、中空円筒状の超硬合金材料の切れ刃を有する組立体が２本以上必要な場合においても、単一の組立体の場合と同等な組み付け精度が得られるものとなった。なお、この場合、請求項４に記載の場合とは異なり、固定部材は両方共、本体とは着脱可能にするのはいうまでもない。また、請求項２に記載の前つかみ側の合金鋼製の固定部材にワークに設けられた前加工溝に嵌合可能に長手方向に延びる案内部を設けるのがよい。これにより、前述したと同様に、ワークの回転方向を適切に位置決めすれば、ワークの前加工溝に案内部、ブローチ刃部の回転位相を合わせることができる。なお、当接面は平面が加工が容易で精度も高いが、軸直角方向の誤差が残る。これに対して同軸の円錐面とすれば、軸方向及び軸直角方向の両方向の取付誤差が小さくなる。一方、球面座のようなものは面同士が均一当たりとなるなどの利点があるが、軸に対して傾きを是正できないので好ましくない。
【００１３】
かかる組立ブローチは、取りしろが少なく高精度を要し、また、超硬合金製の組立体を用いて加工しなければならないような、表面硬度が４５ＨＲＣ以上６５ＨＲＣ以下のような高硬度材の加工に適している。そこで、請求項６に記載の発明においては、請求項１乃至５のいずれか一に記載のブローチを用い、硬度ＨＲＣ（ロックウエル硬さＣスケール）４５以上６５以下の高硬度材の加工を行うブローチ加工方法を提供することにより前述した課題を解決した。
【００１４】
【発明の実施の形態】
以下、本発明にかかる組立ブローチの第一の実施の形態について、図を参照して説明するが、本発明はこれに限定されるわけではない。第一の実施の形態は案内部を兼用した前つかみ部側の固定部材を本体と一体に形成し、かつブローチ本体に着脱可能に本体とは別体のリング状の鍔部（間座）を設け、後つかみ部側から組立体を嵌挿組み付けるようにしたものである。図１は、本発明の第一の実施の形態を示す超硬組立ブローチの一部を切り欠いた側面図、図２は図１に記載の前つかみ部側の組立体の一部を切り欠いた（ａ）は側面図、（ｂ）は正面図、（ｃ）は背面図、図３は図１に記載の後つかみ部側の組立体の一部を切り欠いた（ａ）は側面図、（ｂ）は正面図、（ｃ）は背面図、図４は本発明の実施の形態を示す鍔部の（ａ）は側面図、（ｂ）は正面図である。図２，図３に示す組立体は従来の組立ブローチでも使用しているものである。図１に示すように、組立ブローチ１０の本体１は合金鋼を用いて製作されており、一端に組立ブローチ１０を引き抜くための前つかみ部２、他端に後つかみ部３が形成されている。また、前つかみ部の反対側に棒状の嵌合部４が設けられ、２つの超硬合金製の組立体３１，４１が嵌合可能にされ、２つの組立体の間には合金鋼製の鍔部（間座）９が嵌合部４に嵌合しつつ挟持されている。ブローチ本体１は図１０に示す従来例の本体５１と同様であるが軸方向長さが鍔部９が増えた分に応じて長くなっている。前つかみ部２と棒状の嵌合部４の間に前つかみ側固定部材７が本体１と一体に形成されている。この前つかみ側固定部材７は図示しないワークに設けられた前加工溝に嵌合可能に長手方向に延びた案内部７ｂが設けられている。前つかみ部側固定部材７の嵌合部側端面は軸直角平面部７ｄと二面幅形状を有する凸部７ｅとが設けられている。また、嵌合部４と後つかみ部３との間にはねじ６が設けられている。
【００１５】
図１，２に示すように、前つかみ部側固定部材７の端面の軸直角平面部７ｄに前つかみ部側組立体３１が軸直角平面部３１ａを当接させながらが嵌合部４に嵌合されている。前つかみ部側組立体３１は切れ刃３２の一部または全部が超硬合金で組立体として一緒に焼結されている。前つかみ部側組立体３１の切れ刃３２の前には、前つかみ部側固定部材７の案内部７ｂと位相が一致した組立体案内部３３が形成され、ワークがスムースに切れ刃に誘導される。前つかみ部側組立体３１の両端面はそれぞれ軸直角平面部３１ａ，３１ｂと二面幅形状の凹部３１ｃ，３１ｄとが形成され、一方の凹部３１ｃは前つかみ部側固定部材７の凸部７ｅと嵌合され互いに回転しないように、かつ位相が一致するようにされている。図１，４に示すように、前つかみ部側組立体３１の他方の端面の軸直角平面部３１ｂに当接するように鍔部９が嵌合部４に嵌合されている。鍔部の両端面はそれぞれ軸直角平面部９ａ，９ｂと二面幅形状の凸部９ｃ，９ｄとが形成され、一方の凸部９ｃは前つかみ部側組立体３１の他方の凹部３１ｄと嵌合され互いに回転しないように、かつ位相が一致するようにされている。
【００１６】
図１，３に示すように鍔部９の他方の端面の軸直角平面部９ｂに後つかみ部側組立体４１が軸直角平面部４１ａを当接させながら嵌合部４に嵌合されている。組立体４１の両端面はそれぞれ軸直角平面部４１ａ，４１ｂと二面幅形状の凹部４１ｃ，４１ｄとが形成され、一方の凹部４１ｃは鍔部９の他方の凹部９ｄと嵌合され互いに回転しないように、かつ位相が一致するようにされている。また、後つかみ部側組立体４１も切れ刃４２の一部または全部が超硬合金で組立体として一緒に焼結されている。他方の凹部４１ｄはなくてもよい。図１に示すように、後つかみ部側組立体４１の他方の軸直角平面部４１ｂ、即ち、最外側端面に当接するように後つかみ部側の固定部材として、ダブルナット８を構成するナットが本体１に設けられたねじ６に螺着されている。
【００１７】
組立にあたっては、組立ブローチ１０は、前つかみ部側組立体３１を、後つかみ部３側から、本体１上に設けられた棒状の嵌合部４に嵌入し、前つかみ部側固定部材７の端面７ｄに当接させ、次に、鍔部９を嵌合部４に嵌入し、次に、後つかみ部側組立体４１を嵌合部４に嵌入し、ダブルナット８で挟持固定することにより、組立ブローチ１０を形成する。
【００１８】
従来ブローチにおいては、図９，１０に示すように、切れ刃３２，３４を有する超硬合金の組立体３１，４１は、ブローチ本体５１の前つかみ部側の固定部材７の端面７ｄに押し当て、ダブルナット（後つかみ部側固定部材）８で固定されている。このとき、２つの組立体３１，４１は、合わせ面３１ｂ，４１ａで接触しており、ブローチ加工による振動が原因となって、合わせ面にチッピング、欠けを引き起こすことがあった。これと比較して、図１で示す本発明の組立ブローチ１０では、前つかみ部側組立体３１と後つかみ部側組立体４１の間に、合金鋼の鍔部（間座）９を設けたので、硬度の高い超硬合金同士の接触部が無くなっている。このような組立ブローチ１０を用いて、硬度６０ＨＲＣの高硬度材のブローチ加工を行ったところ、比較的硬度の低い合金鋼が緩衝材となって、組立体３１，４１のチッピング、欠けの発生を防止できた。また、組立体３１，４１と鍔部９は、凹凸部７ｅ，３１ｃ，３１ｄ，９ｃ，９ｄ，４１ａにより互いに回転方向の位置決めが保証されているので、前記組立体の刃部３２，４２の回転位相決めができるものとなっている。
【００１９】
本発明の第二の実施の形態について述べる。第二の実施の形態においては、後つかみ部側固定部材を合金鋼製のブローチ本体と一体に形成し、案内部と兼用した前つかみ部側固定部材をブローチ本体に着脱可能にし、かつダブルナットと案内部材とに二分した場合のものである。図５は本発明の第二の実施の形態を示す超硬組立ブローチの一部を切り欠いた側面図、図６は第二の実施の形態に用いる固定部材の案内部の（ａ）は側面図、（ｂ）は正面図である。第二の実施の形態においては、第一の実施の形態と同様な部分については同符号を付し説明の一部を省略する。図５，６に示すように、組立ブローチ２０の本体１１は合金鋼を用いて製作されており、一端に組立ブローチ２０を引き抜くための前つかみ部２が形成されている。また、本体１１に続いて設けられた棒状の嵌合部４には超硬ブローチ２０の進行方向後側（図でみて上側）に、後つかみ部３が設けられ、後つかみ部と嵌合部の間に後つかみ部側固定部材１８が本体と一体に形成されている。後つかみ部側固定部材１８の嵌合部側端面は軸直角平面部１８ａと二面幅形状を有する凸部１８ｃとが設けられている。また、嵌合部４と前つかみ部２との間にはねじ５が設けられている。後つかみ部側固定部材１８の端面の軸直角平面部１８ａに後つかみ部側組立体４１の他方の端面の軸直角平面部４１ｂが当接するように後つかみ部側組立体が嵌合部４に嵌合されている。後つかみ部側組立体の一方の端面の軸直角平面部４１ａに鍔部（間座）９の他方の端面９ｂが当接するように鍔部が嵌合部４に嵌合されている。鍔部９の一方の端面の軸直角平面部９ａに前つかみ部側組立体３１の他方の端面３１ｂが当接するように前つかみ部側組立体が嵌合部４に嵌合されている。
【００２０】
前つかみ部側組立体３１の一方の軸直角平面部３１ａ、即ち、最外側端面に当接するように、図６に示す案内部材１７ａの端面７ｄが当接するようにされ、案内部材とダブルナット１７ｃとで、前つかみ部側固定部材１７が形成されている。ダブルナット１７ｃは本体１１に設けられたねじ５に螺着されている。案内部材１７ａは本体１１の嵌合部４に嵌合可能にされ、図示しないワークに設けられた前加工溝に嵌合可能に長手方向に延びた案内部７ｂが設けられている。また、案内部材１７ａの嵌合部側端面は軸直角平面部７ｄと二面幅形状を有する凸部７ｅとが設けられている。
【００２１】
組立にあたっては、図２乃至図６に示すように、組立ブローチ２０は、後つかみ部側組立体４１を、前つかみ部２側から本体１１上に設けられた棒状の嵌合部４に嵌入し、後つかみ部側固定部材１８の端面１８ａに当接させ、次に、鍔部９を嵌合部４に嵌入し、次に、前つかみ部側組立体３１を嵌合部に嵌入し、さらに、案内部材１７ａを嵌合部に嵌挿し、ダブルナット１７ｃで挟持固定することにより、組立ブローチを形成する。後つかみ部側固定部材１８端面、後つかみ部側組立体４１、鍔部９、前つかみ部側組立体３１のそれぞれの端面、案内部材１７ａの端面は互いに凹凸部１８ｃ，４１ｄ，４１ｃ，９ｄ，９ｃ，３１ｄ，３１ｃ，７ｅで、互いに回転しないように、かつ位相が一致するようにされている。
【００２２】
かかる第二の実施の形態においても、第一の実施の形態の場合と同様、超硬合金製の組立体３１，４１の間に、合金鋼の鍔部（間座）９を設けたので、硬度の高い超硬合金同士の接触部が無くなり、比較的硬度の低い合金鋼が緩衝材となって、チッピング、欠けの発生を防止するものとなる。なお、組立体が２個、鍔部が１個の場合について説明したが、鍔部を両側に組立体を配置し、最外側の組立体の両端を固定部材で挟持固定することが重要であり、組立体は３個以上、鍔部も２個以上であってもよいことはいうまでもない。
【００２３】
本発明の第三の実施の形態について述べる。第三の実施の形態においては、前後両側のつかみ部側固定部材をブローチ本体とは着脱可能にして、鍔部を合金鋼製のブローチ本体と一体に形成し、鍔部の両側から組立体を嵌挿組み付けするようにしたものである。図７は本発明の第三の実施の形態を示す超硬組立ブローチの一部を切り欠いた側面図、図８は第三の実施の形態に用いる合金鋼製のブローチ本体の（ａ）側面図、（ｂ）は（ａ）のＡ−Ａ線断面図である。第三の実施の形態において、前つかみ部側固定部材１７は第二の実施の形態で述べたと同じく図６に示す案内部材１７ａ及びダブルナット１７ｃを使用している。また、後つかみ部側固定部材は第一の実施の形態で述べたと同じくダブルナット８を使用している。そこで、第一及び第二の実施の形態と同様な部分については同符号を付し説明の一部を省略する。第三の実施の形態においては、ブローチ本体２１は、図８に示すように、合金鋼製で前つかみ部２と、前つかみ部より延びる嵌合部４と、嵌合部を二分する鍔部２９が備えられている。嵌合部４と前つかみ部２の間及び嵌合部と後つかみ部３との間にねじ５，６が設けられている。鍔部２９は本体２１と一体に形成され鍔部の両端には本体の軸に対して直角平面部９ａ，９ｂと凸部９ｃ，９ｄとが形成されている。
【００２４】
図７に示すように、前つかみ部２側には鍔部２９の前つかみ部側直角平面部９ａ及び凸部９ｃと当接及び嵌合して案内部３３を有する前つかみ部側組立体３１、案内部７ｂを有する固定部材１７ａ、ダブルナット１７ｃが順に配設されている。後つかみ部３側には鍔部２９の後つかみ部側直角平面部９ｂ及び凸部９ｄと当接及び嵌合して後つかみ部側組立体４１、ダブルナット８が順に配設され、組立ブローチ３０を構成している。
【００２５】
組立にあたっては、後つかみ部側組立体４１を、後つかみ部３側から本体２１上に設けられた棒状の嵌合部４に嵌入し、組立体端面４１ａ及び凹部４１ｃを鍔部２９の後つかみ部側直角平面部９ｂ及び凸部９ｄに当接嵌合させ、後つかみ側ダブルナット８を後つかみ部側ねじ６に螺着して鍔部２９と固定部材であるダブルナット８により後つかみ部側組立体４１を挟持固定する。また、前つかみ部側組立体３１を、前つかみ部２側から本体２１上に設けられた棒状の嵌合部４に嵌入し、組立体端面３１ｂ及び凹部３１ｄを鍔部２９の前つかみ部側直角平面部９ａ及び凸部９ｃに当接嵌合させ、さらに、案内部材１７ａを組立部材３１に当接、嵌合させ、前つかみ側ダブルナット１７ｃを前つかみ側ねじ５に螺着して鍔部２９と固定部材１７である案内部材１７ａとダブルナット１７ｃにより前つかみ部側組立体３１を挟持固定する。後つかみ部側組立体４１、鍔部２９、前つかみ部側組立体３１のそれぞれの端面４１ａ，９ｂ，９ａ，３１ｂ，３１ａ、案内部材１７ａの端面７ｄは互いに軸直角平面にされ、かつ、凹凸部４１ｃ，９ｄ，９ｃ，３１ｄ，３１ｃ，７ｅで、互いに回転しないように、かつ位相が一致するようにされている。
【００２６】
図９，１０に示す従来型組立ブローチ５０は、嵌合部４より前つかみ部側組立体３１、後つかみ部側組立体４１を順に入れ、ダブルナット８により締め付け、固定するようになっているため、組立体３１，４１の組み付け後の傾きは、同組立体の端面の直角度が相互に影響し合うので、ブローチの傾きが大きくなるものとなっている。これと比較して、本発明の第三の実施の形態においては、本体前つかみ部２側から前つかみ部側組立体３１、案内部７ｂを設けた案内部材１７ａを順に入れ、本体２１に一体にされた鍔部２９の直角平面９ａに組立体３１の端面３１ｂを当接させながらダブルナット１７ｃにより締め付けを行い、また、後つかみ部３側から後つかみ側組立体４１を入れ、本体２１に一体にされた鍔部２９の直角平面９ｂに組立体の端面４１ａを当接させながらダブルナット８により締め付けを行うので、円筒状の超硬合金の組立体の端面直角度が、組み付け後の傾きに影響することがなくなり、単一の組立体の場合と同等な組み付け精度（ブローチ傾き）が得られるものとなった。なお、コスト面は上がるが、直角平面より軸心を通る凹凸の円錐面同士を嵌合させることにより精度をさらに高くできる。また、鍔部は１箇所であるが、支障のない範囲で組立体は複数設けても良く、また、第一、第二の実施の形態で述べたような本体とは着脱可能なリング状の鍔部を組立体の間に設けてもよい。また、仕上げ精度を確保するため、後つかみ部側から入れる組立体４１を刃数の少ない仕上げブローチとし、この部分のみを取外し交換するようにした場合には、前つかみ部側の組立体の組付精度を損なうことなく仕上げブローチ側の取り外し交換、組付が容易にできるので、加工寸法の維持が容易になる。
【００２７】
【発明の効果】
本発明によれば、複数の超硬合金の切れ刃の付いた組立体の間に、合金鋼の鍔部（間座）を設たブローチ工具としたので、加工時の振動による、組立体の接触面のチッピング、欠けの発生を防止するものとなった（請求項１）。
【００２８】
また、案内部を設けた組立体を切れ刃の付いた組立体に続いて嵌合部に挿入したので、ワークに設けられた前加工溝に嵌合を容易にした（請求項２）。また、鍔部又は固定部材の一部を本体と一体にし。鍔部、切れ刃の付いた複数の組立体、複数の固定部材がキーなどの回転方向位置決め手段により回転方向の位置決め及び固定が確実にされるので組み付け精度が高くなり、加工精度が向上する。（請求項３）。また、固定部材のいずれか一方を本体と一体にしたので、本体への組立体の固定が確実になった（請求項４）。
【００２９】
さらに、鍔部を棒状の嵌合部を二分するように設け鍔部を挟んで両側に組立体を配置し、互いに軸直角平面又は同軸の円錐面で当接するようにしたので、各々の組立体の端面直角度が、組み付け後の傾きに影響しあうことがなくなり、単一の組立体の場合と同等な組み付け精度が得られ、加工精度、特にスプラインの歯筋精度、直角度が安定するものとなった。
【００３０】
かかる、本発明の組立ブローチにより、硬度が４５ＨＲＣ以上６５ＨＲＣ以下の高硬度材のブローチ加工方法により、加工負荷が大きく振動が発生しやすい４５〜６５ＨＲＣの高硬度材のブローチ加工においても、チッピングが発生せず、倒れのない良好な加工を得ることができた。
【図面の簡単な説明】
【図１】本発明の第一の実施の形態を示す超硬組立ブローチの一部を切り欠いた側面図である。
【図２】組立ブローチの前つかみ部側の組立体の一部を切り欠いた（ａ）は側面図、（ｂ）は正面図、（ｃ）は背面図である。
【図３】組立ブローチの後つかみ部側の組立体の一部を切り欠いた（ａ）は側面図、（ｂ）は正面図、（ｃ）は背面図である。
【図４】本発明の第一の実施の形態を示す鍔部の（ａ）は側面図、（ｂ）は正面図である。
【図５】本発明の第二の実施の形態を示す超硬組立ブローチの一部を切り欠いた側面図である。
【図６】本発明の第二の実施の形態に用いる固定部材の案内部の（ａ）は側面図、（ｂ）は正面図である。
【図７】本発明の第三の実施の形態を示す超硬組立ブローチの一部を切り欠いた側面図である。
【図８】本発明の第三の実施の形態に用いる合金鋼製のブローチ本体の（ａ）は側面図、（ｂ）は（ａ）のＡ−Ａ線断面図である。
【図９】従来の超硬組立ブローチの一部を切り欠いた側面図である。
【図１０】従来の超硬組立ブローチの案内部を有する前つかみ部側固定部材が一体にされたブローチ本体の側面図である。
【符号の説明】
１、１１、２１本体
２前つかみ部
４嵌合部
７、１７（前つかみ部側）固定部材
７ｂ案内部
７ｄ，３１ａ固定部材と組立体との当接部
８、１８（後つかみ部側）固定部材
９、２９鍔部（間座）
９ａ、９ｂ、３１ｂ、４１ａ鍔部と組立体との当接部
１０、２０、３０組立ブローチ。
３１、４１組立体
３２、４２切れ刃
３１ａ、４１ｂ最外側端面[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a broach in which a number of cutting edges are arranged in the axial direction on the outer periphery of a main body, and more particularly to an assembling broach in which the material of the cutting edges is a cemented carbide (carbide). Further, the present invention relates to an assembly broach suitable for processing a hard material having a Rockwell hardness of, for example, 50 HRC or more after quenching.
[0002]
[Prior art]
In the conventional broaching, a workpiece (hereinafter, referred to as a workpiece) having a hardness of 20 to 30 HRC (Rockwell hardness C scale: the same applies hereinafter) is performed. For this reason, the work is often subjected to heat treatment for increasing the hardness after broaching. At this time, the hardness of the quenched portion is about 60 HRC, and the carburizing depth is about 1 mm. However, since heat treatment distortion occurs when carburizing and quenching, the target shape is determined in advance in consideration of the deformation of the heat treatment, and the workpiece before quenching is processed. However, since the amount of deformation is unstable, there has been a problem that, for example, the accuracy (diameter, tooth trace, pitch, etc.) of the involute spline after quenching does not become the target shape. Therefore, as means for solving this, in the broach described in Patent Document 1, as shown in FIGS. 9 and 10, a fixing member 7 having a guide portion 7 b provided following the front grip portion 2 is used. Assemblies 31 and 41 having cutting edges 32 and 42 of a hollow cylindrical cemented carbide material in a body 51 having a fitting portion 4 extending to the rear grip portion 3 are connected to the rear grip portion 3 and the fitting portion 4. An assembly broach 50 having a structure in which a double nut 8 is screwed onto a screw 6 provided therebetween and clamped and fixed is shown. This assembling broach has a large cutting length of a hollow cylindrical cemented carbide material because the required broach length is long when the heat treatment distortion of the work is large and a large cutting margin is required. , 42 are sequentially inserted from one side (rear grip portion side) of the broach body 51, and the assembly is clamped and fixed by the fixing member 8 such as a double nut.
[0003]
[Patent Document 1] JP-A-2002-137118
[0004]
[Problems to be solved by the invention]
However, when two or more assemblies 31 and 41 having cutting edges 31 and 42 of cemented carbide material are inserted and assembled in order, vibration caused by broaching causes the mating surfaces (contact surfaces) of the assemblies. 31b and 41a have a problem of causing chipping and chipping. In addition, the inclination of the assembly broach after assembly affects the inclination of the other assembly if the perpendicularity of the end face of one assembly is poor. That is, since the mutual squareness error affects the inclination of the broach after assembling, there is a problem that better assembling accuracy (brooch inclination) cannot be obtained as compared with the case where only one assembly is used. . This has had an adverse effect on the processing accuracy, particularly on the accuracy of the spline tooth traces and the squareness.
[0005]
SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the related art, and in an assembly broach requiring two or more assemblies having cutting edges, chipping of an assembly contact surface by broaching vibration. , To provide a brooch that does not cause chipping. It is another object of the present invention to provide a broach in which the inclination of the broach after assembling is small and the performance is equivalent to that of a single assembly.
[0006]
[Means for Solving the Problems]
As a result of the research, the present inventors performed a processing test on a work having a hardness of 60 HRC using a broach tool disclosed in Patent Document 1 with two assemblies, and found that vibration caused by broaching was caused. Focusing on the fact that chipping and chipping of the mating surface of the assembly that occurs when the assembly having cutting edges is made of alloy steel is unlikely to occur, but is likely to occur when it is made of cemented carbide, It is considered that depending on the contact area (contact state), high stress is applied partially to cause chipping, and it is sufficient to provide a buffering effect by sandwiching an alloy steel having a lower hardness than the assembly on the mating surface of the assembly. I thought. According to this idea, in the present invention, an inner broach in which a number of cutting edges having a front grip portion are arranged in dimensional order, wherein the main body made of alloy steel having the front grip portion has a rod-like shape opposite to the front grip portion. An assembly broach tool having a plurality of hollow cylindrical or ring-shaped cemented carbide assemblies having cutting edges at the fitting portion, wherein the fitting portion has a cutting edge. And one or more alloy steel flanges (spacers) for dividing the assembly. The assembly is divided and disposed on both sides of the flange, and the assembly and the flange are separated from each other by the outermost one of the assemblies. The above-mentioned problem has been solved by providing an assembling broach in which an alloy steel fixing member is provided to abut and fix the outermost end surfaces of the two outer assemblies.
[0007]
That is, a part made of an assembly of two cemented carbides and a main body having a grip part made of an alloy steel are integrally assembled into one broach, and a flange of the alloy steel is provided between the plurality of assemblies. Seats), so there is no contact between cemented carbides with high hardness, and alloy steel with relatively low hardness becomes a buffer material, and due to the variation around the contact surface, it is partially high. No stress was applied, and chipping and chipping were prevented. In addition, it is preferable to provide a flange between all the assemblies except the fixing member, but it may be a part.
[0008]
In addition, the guide portion has no cutting edge, does not need to be hard with respect to the work, and wants to facilitate positioning. Therefore, in the invention as set forth in claim 2, the fixing member on the front gripping portion side has a guide portion extending in the longitudinal direction so as to be fittable in a pre-machining groove provided in a workpiece (work). Assembling brooch. As a result, the guide portion fits into the pre-machining groove of the work, and the phase and the positioning of the work and the broach are automatically performed. Further, since the cylindrical cemented carbide assembly having a blade portion and the guide portion of the fixing member made of alloy steel can be exchanged according to the processing specifications of the work, it is easy to cope with various kinds of work. In addition, if the guide portion has a tapered shape that reduces the diameter of the distal end portion, the guide portion can be more easily fitted.
[0009]
Further, in the invention according to claim 3, the contact portion between the flange portion and the assembly and the contact portion between the fixing member having the guide portion and the assembly each have a rotational direction. The positioning means is positioned relative to each other so as not to rotate in the rotation direction, and is positioned or fixed to the main body so that one or more of the flange and the fixing member do not rotate with respect to the main body. Thereby, the main body having the front grip portion, and the flange portion, the assembly, and the fixing member are positioned so as not to rotate relative to each other with respect to the flange portion or the fixing member fixed to the main body. All of the assembly and the flange are fixed. Therefore, by regulating and grasping the front grip portion of the broach so that the rotation angle becomes the same, the rotation phase of the guide portion and the blade portions provided on the plurality of assemblies can be determined. Accordingly, if the rotation direction of the work is properly positioned, the rotation phases of the guide portion and the broach blade can be matched with the pre-machining groove of the work.
[0010]
In addition, we want to fix it to the main unit as securely as possible. Therefore, in the invention described in claim 4, one of the fixing members is formed integrally with the main body. Thus, the rotation of the assembly and the flange is reliably prevented.
[0011]
On the other hand, as described above, the present inventors performed a processing test on a work using two assemblies and having a hardness of 60 HRC and evaluated the processing accuracy. Focusing on the assembling state of the broach, the inclination of the posture assembled with the main body of the cylindrical broach having the carbide blades was larger in the case of two assemblies than in the case of one, and the machining was performed. I learned that the spline precision and the squareness of the spline of the work would be worse. The same applies to the case where the above-mentioned alloy steel flange is separated from the main body. According to this knowledge, in the present invention according to claim 5, the flange portion is provided only at one place and is integrated with the main body, and the contact surface between the assembly and the flange portion and the assembly and the The above-mentioned problem has been solved by providing an assembly broach in which the contact surface with the fixing member is a plane perpendicular to the axis or a coaxial conical surface.
[0012]
In other words, the fitting portion is divided in an assembly broach in which a portion made of a cemented carbide assembly and a main body having a front grip portion made of alloy steel are fitted into a fitting portion and integrally assembled into one broach. A flange part made of alloy steel integral with the main body is provided, an assembly on the front grip part side is incorporated from the front grip part side, and the flange is brought into contact with a plane perpendicular to the axis or a coaxial conical surface of the flange part, and the other side. The assembly is assembled so that it comes into contact with the flange from the rear grip (opposite to the front grip) by a plane perpendicular to the axis or a coaxial conical surface, and furthermore, both ends are clamped and fixed by fixing members. The edge perpendicularity of the alloy assembly does not affect the tilt of the other assembly after assembly. Therefore, even when two or more assemblies each having a cutting edge made of a hollow cylindrical cemented carbide material are required, assembling accuracy equivalent to that of a single assembly can be obtained. In this case, it is needless to say that, unlike the case described in claim 4, both of the fixing members are detachable from the main body. Further, it is preferable to provide a guide portion extending in the longitudinal direction so as to be able to fit into a pre-machining groove formed in the work on the alloy steel fixing member on the front grip side according to the second aspect. Thus, similarly to the above, if the rotation direction of the work is properly positioned, the rotation phase of the guide portion and the broach blade portion can be matched with the pre-machining groove of the work. The contact surface has a flat surface that is easy to machine and has high accuracy, but an error in the direction perpendicular to the axis remains. On the other hand, if a conical conical surface is used, mounting errors in both the axial direction and the direction perpendicular to the axis are reduced. On the other hand, a spherical seat has the advantage that the surfaces are evenly contacted with each other, but it is not preferable because the inclination with respect to the axis cannot be corrected.
[0013]
This assembling broach requires a small amount of clearance, requires high precision, and requires machining using a cemented carbide assembly. The machining of a hard material having a surface hardness of 45 HRC or more and 65 HRC or less. Suitable for. Therefore, in the invention according to claim 6, a broach for processing a high-hardness material having a hardness HRC (Rockwell hardness C scale) of 45 to 65 using the broach according to any one of claims 1 to 5. The problem described above has been solved by providing a processing method.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a first embodiment of an assembly broach according to the present invention will be described with reference to the drawings, but the present invention is not limited thereto. In the first embodiment, a fixing member on the front grip portion side also serving as a guide portion is formed integrally with the main body, and a ring-shaped flange (spacing) separate from the main body is detachably attached to the broach main body. The assembly is inserted and assembled from the rear grip portion side. FIG. 1 is a side view in which a part of a carbide assembling broach according to a first embodiment of the present invention is cut away, and FIG. 2 is a view in which a part of an assembly on a front grip portion side shown in FIG. (A) is a side view, (b) is a front view, (c) is a rear view, and FIG. 3 is a cutaway view of a part of an assembly on a rear grip portion side described in FIG. 1 (a) is a side view. 4 (b) is a front view, FIG. 4 (c) is a rear view, FIG. 4 is a side view, and FIG. 4 (b) is a front view of a flange showing an embodiment of the present invention. The assembly shown in FIGS. 2 and 3 is also used in a conventional assembly broach. As shown in FIG. 1, the main body 1 of the assembly broach 10 is made of alloy steel, and has a front grip 2 for pulling out the assembly broach 10 at one end and a rear grip 3 at the other end. . Further, a bar-shaped fitting portion 4 is provided on the opposite side of the front grip portion, so that two cemented carbide assemblies 31, 41 can be fitted, and between the two assemblies, alloy steel is provided. A flange (spacing) 9 is held while being fitted to the fitting portion 4. The broach main body 1 is the same as the main body 51 of the conventional example shown in FIG. 10, but the length in the axial direction is increased in accordance with the increase in the flange 9. A front grip side fixing member 7 is formed integrally with the main body 1 between the front grip portion 2 and the rod-shaped fitting portion 4. The front gripping side fixing member 7 is provided with a guide portion 7b extending in the longitudinal direction so as to be able to fit into a pre-machining groove provided in a work (not shown). An end surface on the fitting portion side of the front gripping portion-side fixing member 7 is provided with a flat portion 7d perpendicular to the axis and a convex portion 7e having a width across flats. A screw 6 is provided between the fitting part 4 and the rear grip part 3.
[0015]
As shown in FIGS. 1 and 2, the front grip part-side assembly 31 is fitted to the fitting part 4 while the front grip part-side assembly 31 abuts the axial perpendicular plane part 31 a on the end face of the front grip part-side fixing member 7. Have been combined. In the front grip part side assembly 31, a part or the whole of the cutting edge 32 is sintered together with cemented carbide as an assembly. In front of the cutting edge 32 of the front grip part side assembly 31, an assembly guide part 33 whose phase matches the guide part 7b of the front grip part side fixing member 7 is formed, and the work is smoothly guided to the cutting edge. You. Both end surfaces of the front grip portion side assembly 31 are formed with flat portions 31a, 31b perpendicular to the axis and concave portions 31c, 31d having a two-plane width, respectively, and one concave portion 31c is a convex portion 7e of the front grip portion side fixing member 7. So that they do not rotate with each other and have the same phase. As shown in FIGS. 1 and 4, the flange portion 9 is fitted to the fitting portion 4 so as to abut on the flat surface portion 31 b at the other end surface of the front grip portion side assembly 31. Both end surfaces of the flange portion are formed with flat portions 9a and 9b perpendicular to the axis and convex portions 9c and 9d having a width across flat shape, and one convex portion 9c is fitted with the other concave portion 31d of the front grip portion side assembly 31. They are merged so that they do not rotate with each other, and their phases match.
[0016]
As shown in FIGS. 1 and 3, the rear grip portion side assembly 41 is fitted to the fitting portion 4 while the flat surface portion 41 a is in contact with the flat surface portion 9 b on the other end surface of the flange portion 9. . Both end surfaces of the assembly 41 are formed with flat portions 41a and 41b perpendicular to the axis and recesses 41c and 41d having a two-sided width, respectively. One recess 41c is fitted into the other recess 9d of the flange portion 9 and does not rotate with each other. And the phases are matched. Also, in the rear grip part side assembly 41, a part or the whole of the cutting edge 42 is sintered together as an assembly with a cemented carbide. The other concave portion 41d may not be provided. As shown in FIG. 1, a nut constituting the double nut 8 is used as a fixing member on the rear grip portion side so as to abut on the other flat surface portion 41 b of the rear grip portion side assembly 41, that is, the outermost end face. It is screwed to a screw 6 provided on the main body 1.
[0017]
In assembling, the assembling broach 10 fits the front grip part side assembly 31 from the rear grip part 3 side into the rod-shaped fitting part 4 provided on the main body 1 to form the front grip part side fixing member 7. By contacting the end surface 7d, the flange 9 is fitted into the fitting portion 4, and then the rear grip portion side assembly 41 is fitted into the fitting portion 4 and is clamped and fixed by the double nut 8. The assembly broach 10 is formed.
[0018]
In the conventional broach, as shown in FIGS. 9 and 10, the cemented carbide assemblies 31 and 41 having the cutting edges 32 and 34 are pressed against the end face 7 d of the fixing member 7 on the front grip portion side of the broach body 51. , And is fixed by a double nut (rear gripping portion side fixing member) 8. At this time, the two assemblies 31 and 41 are in contact with each other at the mating surfaces 31b and 41a, and may cause chipping or chipping at the mating surfaces due to vibration caused by broaching. In comparison, in the assembly broach 10 of the present invention shown in FIG. 1, the flange portion (spacing) 9 of the alloy steel is provided between the front grip portion side assembly 31 and the rear grip portion side assembly 41. Therefore, the contact portion between the hard metals having high hardness is eliminated. When broaching of a high-hardness material having a hardness of 60 HRC is performed using such an assembly broach 10, alloy steel having a relatively low hardness becomes a buffer material, and chipping and chipping of the assemblies 31, 41 are prevented. Could be prevented. In addition, since the positioning in the rotational direction of the assemblies 31, 41 and the flange 9 is ensured by the uneven portions 7e, 31c, 31d, 9c, 9d, 41a, the rotation of the blades 32, 42 of the assembly is performed. The phase can be determined.
[0019]
A second embodiment of the present invention will be described. In the second embodiment, the rear grip part side fixing member is formed integrally with the alloy steel broach main body, the front grip part side fixing member also serving as the guide part is detachable from the broach main body, and the double nut And a guide member. FIG. 5 is a side view in which a part of a carbide assembling broach according to a second embodiment of the present invention is cut away, and FIG. 6 is a side view of a guide portion of a fixing member used in the second embodiment. FIG. 2B is a front view. In the second embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and a part of the description is omitted. As shown in FIGS. 5 and 6, the main body 11 of the assembly broach 20 is manufactured using alloy steel, and a front grip portion 2 for pulling out the assembly broach 20 is formed at one end. Further, the bar-shaped fitting portion 4 provided following the main body 11 is provided with a rear grip portion 3 on the rear side (upper side in the drawing) of the carbide broach 20 in the traveling direction, and the rear grip portion and the fitting portion are provided. The rear grip part side fixing member 18 is formed integrally with the main body. An end surface on the fitting portion side of the rear grip portion-side fixing member 18 is provided with a flat portion 18a perpendicular to the axis and a convex portion 18c having a width across flat shape. Further, a screw 5 is provided between the fitting part 4 and the front grip part 2. The rear grip part-side assembly comes into contact with the fitting part 4 such that the axis perpendicular plane part 41b of the other end face of the rear grip part-side assembly 41 abuts on the plane part 18a perpendicular to the axis of the end face of the rear grip part-side fixing member 18. Mated. The flange portion is fitted to the fitting portion 4 such that the other end surface 9b of the flange portion (spacer) 9 abuts on the flat surface 41a perpendicular to the axis on one end surface of the rear grip portion side assembly. The front grip portion side assembly is fitted to the fitting portion 4 such that the other end surface 31b of the front grip portion side assembly 31 abuts on the flat surface portion 9a perpendicular to the axis on one end surface of the flange portion 9.
[0020]
The end face 7d of the guide member 17a shown in FIG. 6 is brought into contact with one of the flat surfaces 31a perpendicular to the axis of the front grip part side assembly 31, that is, the outermost end face. Thus, the front grip portion side fixing member 17 is formed. The double nut 17c is screwed to a screw 5 provided on the main body 11. The guide member 17a is adapted to be fitted to the fitting portion 4 of the main body 11, and is provided with a guide portion 7b extending in the longitudinal direction so as to be fitted to a pre-processed groove provided in a work (not shown). An end surface of the guide member 17a on the fitting portion side is provided with a flat portion 7d perpendicular to the axis and a convex portion 7e having a two-sided width shape.
[0021]
In assembling, as shown in FIGS. 2 to 6, the assembly broach 20 fits the rear grip part side assembly 41 into the rod-shaped fitting part 4 provided on the main body 11 from the front grip part 2 side. The flange 9 is fitted into the fitting portion 4, and then the front grip portion side assembly 31 is fitted into the fitting portion, and then the flange portion 9 is fitted into the fitting portion 4. The assembly broach is formed by fitting the guide member 17a into the fitting portion and holding and fixing the guide member 17a with the double nut 17c. The end surfaces of the rear grip portion-side fixing member 18, the rear grip portion-side assembly 41, the flange 9, the front grip portion-side assembly 31, and the end surface of the guide member 17a are concave and convex portions 18c, 41d, 41c, 9d, respectively. At 9c, 31d, 31c, and 7e, the phases are set so that they do not rotate with each other and coincide with each other.
[0022]
In the second embodiment as well, as in the first embodiment, the flange portion (spacing) 9 made of alloy steel is provided between the assemblies 31 and 41 made of cemented carbide. The contact portion between the high-hardness cemented carbides is eliminated, and the alloy steel having a relatively low hardness serves as a buffer, thereby preventing chipping and chipping. Although the description has been given of the case where there are two assemblies and one flange portion, it is important to arrange the assemblies on both sides of the flange portion and to hold and fix both ends of the outermost assembly with fixing members. Needless to say, the number of assemblies may be three or more and the number of flanges may be two or more.
[0023]
A third embodiment of the present invention will be described. In the third embodiment, the front and rear grip part side fixing members are detachable from the broach body, the flange is formed integrally with the alloy steel broach body, and the assembly is assembled from both sides of the flange. It is designed to be fitted and assembled. FIG. 7 is a side view in which a part of a cemented carbide broach according to a third embodiment of the present invention is cut away, and FIG. 8 is a side view of an alloy steel broach body used in the third embodiment. FIG. 2B is a sectional view taken along line AA of FIG. In the third embodiment, the front grip part side fixing member 17 uses the guide member 17a and the double nut 17c shown in FIG. 6 as described in the second embodiment. Further, as described in the first embodiment, the rear nut side fixing member uses the double nut 8 as described in the first embodiment. Therefore, the same parts as those in the first and second embodiments are denoted by the same reference numerals, and a part of the description is omitted. In the third embodiment, as shown in FIG. 8, the broach main body 21 is made of an alloy steel and has a front grip portion 2, a fitting portion 4 extending from the front grip portion, and a flange portion that bisects the fitting portion. 29 are provided. Screws 5 and 6 are provided between the fitting portion 4 and the front grip portion 2 and between the fitting portion and the rear grip portion 3. The flange 29 is formed integrally with the main body 21, and flat portions 9a, 9b and projections 9c, 9d are formed at both ends of the flange at right angles to the axis of the main body.
[0024]
As shown in FIG. 7, a front grip part side assembly 31 having a guide part 33 on the front grip part 2 side, which is in contact with and fitted to the front grip part side right-angled flat part 9 a and the convex part 9 c of the flange part 29. , A fixing member 17a having a guide portion 7b, and a double nut 17c are arranged in this order. On the rear grip part 3 side, a rear grip part side assembly 41 and a double nut 8 are arranged in order in contact with and fitted to the rear grip part side right-angled flat part 9b and the convex part 9d of the flange part 29, and are sequentially arranged. 30.
[0025]
In assembling, the rear grip part side assembly 41 is fitted into the rod-shaped fitting part 4 provided on the main body 21 from the rear grip part 3 side, and the assembly end face 41 a and the concave part 41 c are gripped rearward by the flange part 29. The rear gripping side double nut 8 is screwed to the rear gripping part side screw 6 by abutment fitting with the flat side part 9b and the convex part 9d on the rear side, and the rear gripping part is fixed by the flange part 29 and the double nut 8 as a fixing member. The side assembly 41 is clamped and fixed. Further, the front grip part side assembly 31 is fitted into the rod-like fitting part 4 provided on the main body 21 from the front grip part 2 side, and the assembly end face 31b and the concave part 31d are connected to the front grip part side of the flange part 29. The guide member 17a is brought into contact with and fitted to the assembly member 31, and the front grip side double nut 17c is screwed into the front grip side screw 5 to form a flange. The front grip portion side assembly 31 is clamped and fixed by the portion 29, the guide member 17a as the fixing member 17, and the double nut 17c. The end faces 41a, 9b, 9a, 31b, 31a of the rear grip part-side assembly 41, the flange 29, the front grip part-side assembly 31, and the end face 7d of the guide member 17a are planes perpendicular to each other. The portions 41c, 9d, 9c, 31d, 31c, and 7e are configured so as not to rotate with each other and to have the same phase.
[0026]
The conventional assembly broach 50 shown in FIGS. 9 and 10 is configured such that the front grip part side assembly 31 and the rear grip part side assembly 41 are sequentially inserted from the fitting part 4, and tightened and fixed by the double nut 8. Therefore, the inclination of the broach becomes large because the right angles of the end faces of the assemblies 31 and 41 affect each other after the assembly. In comparison with this, in the third embodiment of the present invention, the front grip part side assembly 31 and the guide member 17a provided with the guide part 7b are sequentially inserted from the main body front grip part 2 side, and integrated with the main body 21. The end face 31b of the assembly 31 is brought into contact with the right-angled flat surface 9a of the flange portion 29, and the assembly is tightened by the double nut 17c. Since the assembly is tightened by the double nut 8 while the end face 41a of the assembly is brought into contact with the right-angled flat surface 9b of the integrated flange 29, the perpendicularity of the end face of the cylindrical cemented carbide assembly is reduced after the assembly. And the same assembling accuracy (brooch inclination) as in the case of a single assembly can be obtained. Although the cost is increased, the accuracy can be further improved by fitting the conical surfaces of the concavities and convexities passing through the axis from the right-angled plane. Although the number of the flanges is one, a plurality of assemblies may be provided as long as they do not interfere with each other. Further, a ring-shaped assembly detachable from the main body as described in the first and second embodiments. A collar may be provided between the assemblies. Also, in order to secure finishing accuracy, the assembly 41 to be inserted from the rear grip portion side is a finishing broach with a small number of blades, and if only this portion is removed and replaced, the assembly of the front grip portion side assembly The removal and replacement of the finishing broach and the assembling of the finishing broach can be easily performed without deteriorating the mounting accuracy, so that the processing dimensions can be easily maintained.
[0027]
【The invention's effect】
According to the present invention, since the broaching tool is provided with a flange portion (spacer) made of alloy steel between assemblies having a plurality of cutting edges made of cemented carbide, vibration of the assembly caused by machining causes the assembly. This prevents chipping and chipping of the contact surface (claim 1).
[0028]
Further, since the assembly provided with the guide portion is inserted into the fitting portion following the assembly provided with the cutting edge, the fitting into the pre-machining groove provided in the work is facilitated (claim 2). Also, a part of the flange or the fixing member is integrated with the main body. The positioning and fixing of the flange, the plurality of assemblies with cutting edges, and the plurality of fixing members in the rotation direction by the rotation direction positioning means such as a key are ensured, so that the assembling accuracy is increased and the processing accuracy is improved. (Claim 3). Also, since one of the fixing members is integrated with the main body, the assembly is securely fixed to the main body (claim 4).
[0029]
Furthermore, the flanges are provided so as to divide the rod-shaped fitting portion into two parts, and the assemblies are arranged on both sides of the flanges so as to abut each other on a plane perpendicular to the axis or a coaxial conical surface. The perpendicularity of the end face does not affect the inclination after assembling, the same assembling accuracy as that of a single assembly is obtained, and the machining accuracy, especially the spline tooth trace accuracy and the squareness are stable It became.
[0030]
According to the broaching method for a hard material having a hardness of 45 HRC or more and 65 HRC or less according to the assembly broach of the present invention, chipping occurs even in the broaching of a 45 to 65 HRC hard material having a large processing load and easy vibration. Without this, good processing without falling could be obtained.
[Brief description of the drawings]
FIG. 1 is a partially cutaway side view of a carbide assembling broach according to a first embodiment of the present invention.
2A is a side view, FIG. 2B is a front view, and FIG. 2C is a rear view, in which a part of an assembly on a front grip portion side of the assembly broach is cut away.
3A is a side view, FIG. 3B is a front view, and FIG. 3C is a rear view, in which a part of the assembly on the grip side of the assembly broach is cut away.
FIG. 4A is a side view and FIG. 4B is a front view of a flange according to the first embodiment of the present invention.
FIG. 5 is a partially cutaway side view of a cemented carbide broach according to a second embodiment of the present invention.
FIG. 6A is a side view and FIG. 6B is a front view of a guide portion of a fixing member used in the second embodiment of the present invention.
FIG. 7 is a partially cutaway side view of a cemented carbide broach according to a third embodiment of the present invention.
8 (a) is a side view of an alloy steel broach body used in the third embodiment of the present invention, and FIG. 8 (b) is a sectional view taken along line AA of FIG. 8 (a).
FIG. 9 is a side view in which a part of a conventional carbide assembling broach is cut away.
FIG. 10 is a side view of a broach main body in which a front grip side fixing member having a guide portion of a conventional carbide assembly broach is integrated.
[Explanation of symbols]
1, 11, 21 body
2 Front grip
4 Fitting part
7, 17 (front gripping part side) fixing member
7b Guide
7d, 31a Contact portion between fixing member and assembly
8, 18 (Rear grip side) Fixing member
9, 29 Flange (spacing)
9a, 9b, 31b, 41a Contact portion between flange and assembly
10, 20, 30 Assembly brooch.
31, 41 assembly
32, 42 Cutting edge
31a, 41b Outermost end face

Claims

An inner surface broach in which a number of cutting blades having a front grip portion are arranged in dimensional order, wherein the alloy steel main body having the front grip portion has a rod-shaped fitting portion on the opposite side of the front grip portion. In an assembling broach tool in which a plurality of hollow cylindrical or ring-shaped cemented carbide assemblies each having a cutting edge at the fitting portion are fitted and fixed, one or more alloy steels that divide the fitting portion are provided. The assembly is divided and arranged on both sides of the flange, and the assembly and the flange are respectively applied to outermost end faces of two outermost assemblies of the assembly. An assembling broach, wherein a fixing member made of an alloy steel to be held in contact with and fixed is provided.

2. The assembly according to claim 1, wherein the fixing member on the front gripping portion side has a guide portion extending in a longitudinal direction so as to be fittable in a pre-machining groove provided in the workpiece. 3. brooch.

The abutting portion between the flange portion and the assembly, and the abutting portion between the fixing member having the guide portion and the assembly are positioned with respect to each other so as not to rotate in the rotation direction by rotation direction positioning means. The assembly broach according to claim 2, wherein one or more of the flange portion and the fixing member are positioned or fixed to the main body so as not to rotate with respect to the main body.

The assembly broach according to claim 3, wherein one of the fixing members is integrated with the main body.

The flange portion is provided only at one position and is integrated with the main body, and a contact surface between the assembly and the flange portion and a contact surface between the assembly and the fixing member have a plane perpendicular to an axis or The assembly broach according to claim 1 or 2, wherein the broach is coaxially conical.

A broaching method characterized by using the broach according to any one of claims 1 to 5 to process a high-hardness material having a hardness of 45 HRC to 65 HRC (Rockwell hardness C scale) or less.